18409723 has 2 divisors, whose sum is σ = 18409724. Its totient is φ = 18409722.

The previous prime is 18409673. The next prime is 18409747. The reversal of 18409723 is 32790481.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18409723 is a prime.

It is not a weakly prime, because it can be changed into another prime (18409763) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9204861 + 9204862.

It is an arithmetic number, because the mean of its divisors is an integer number (9204862).

Almost surely, 2^18409723 is an apocalyptic number.

18409723 is a deficient number, since it is larger than the sum of its proper divisors (1).

18409723 is an equidigital number, since it uses as much as digits as its factorization.

18409723 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 18409723 is about 4290.6553112549. The cubic root of 18409723 is about 264.0477176908.

The spelling of 18409723 in words is "eighteen million, four hundred nine thousand, seven hundred twenty-three".